scholarly journals Mathematics and biology: a Kantian view on the history of pattern formation theory

2011 ◽  
Vol 221 (5-6) ◽  
pp. 255-279 ◽  
Author(s):  
Siegfried Roth
Keyword(s):  
Pattern Formation ◽  
Formation Theory ◽  
History Of ◽  
Kantian View

scholarly journals Spatial Heterogeneity and Imperfect Mixing in Chemical Reactions: Visualization of Density-Driven Pattern Formation

2009 ◽  
Vol 2009 ◽  
pp. 1-4 ◽  
Author(s):  
Sabrina G. Sobel ◽  
Harold M. Hastings ◽  
Matthew Testa
Keyword(s):  
Pattern Formation ◽  
Salt Water ◽  
Model System ◽  
Reaction Vessel ◽  
Chemical System ◽  
Industrial Processes ◽  
History Of ◽  
Convection Rolls ◽  
Belousov Zhabotinsky Reaction ◽  
Complex Ion

Imperfect mixing is a concern in industrial processes, everyday processes (mixing paint, bread machines), and in understanding salt water-fresh water mixing in ecosystems. The effects of imperfect mixing become evident in the unstirred ferroin-catalyzed Belousov-Zhabotinsky reaction, the prototype for chemical pattern formation. Over time, waves of oxidation (high ferriin concentration, blue) propagate into a background of low ferriin concentration (red); their structure reflects in part the history of mixing in the reaction vessel. However, it may be difficult to separate mixing effects from reaction effects. We describe a simpler model system for visualizing density-driven pattern formation in an essentially unmixed chemical system: the reaction of pale yellow Fe3+ with colorless SCN− to form the blood-red Fe(SCN)2+ complex ion in aqueous solution. Careful addition of one drop of Fe(NO3)3 to KSCN yields striped patterns after several minutes. The patterns appear reminiscent of Rayleigh-Taylor instabilities and convection rolls, arguing that pattern formation is caused by density-driven mixing.

The Effect of Teaching Word Formation Theory to English Students

2017 ◽  
Vol 7 (1) ◽  
pp. 7
Author(s):  
Miranda Enesi
Keyword(s):  
Teaching And Learning ◽  
English Language ◽  
Language Teaching ◽  
English Word ◽  
Word Formation ◽  
English Language Teaching ◽  
Formation Theory ◽  
Building Process ◽  
History Of ◽  
English Students

The word-formation theory is often avoided in English language course books and little research is conducted on the pedagogical status of word-building process. However, many researchers and lecturers have realized the effect of teaching word-formation theory in English languages course books. English language lecturers have noted that vocabulary is very important in various subjects of English language branch curricula. For this reason, we must admit that the processes of word-formation, through which every language vocabulary can be enriched, are very important in English language teaching and learning. Word formation components such as prefixes, suffixes, etymology, history of words and other required materials in composing the vocabulary of English language are tested in Aleksandër Moisiu University. The results have revealed a significant and successful effect of teaching Word formation theory, this way showing the colossal importance of this important language aspect in every English language edition course book. This paper has two aims: first to review types of English word-formation and, second, to discuss the absence and the need for word-formation theory in English language course books. Keywords: Word formation, prefixes, suffixes, words, vocabulary.

scholarly journals Discovery of fairy circles in Australia supports self-organization theory

2016 ◽  
Vol 113 (13) ◽  
pp. 3551-3556 ◽  
Author(s):  
Stephan Getzin ◽  
Hezi Yizhaq ◽  
Bronwyn Bell ◽  
Todd E. Erickson ◽  
Anthony C. Postle ◽  
...  
Keyword(s):  
Pattern Formation ◽  
Organization Theory ◽  
Bare Soil ◽  
Self Organization ◽  
Homogeneous Distribution ◽  
Small Scale ◽  
Water Runoff ◽  
Driving Mechanism ◽  
Spatial Pattern Analysis ◽  
Formation Theory

Vegetation gap patterns in arid grasslands, such as the “fairy circles” of Namibia, are one of nature’s greatest mysteries and subject to a lively debate on their origin. They are characterized by small-scale hexagonal ordering of circular bare-soil gaps that persists uniformly in the landscape scale to form a homogeneous distribution. Pattern-formation theory predicts that such highly ordered gap patterns should be found also in other water-limited systems across the globe, even if the mechanisms of their formation are different. Here we report that so far unknown fairy circles with the same spatial structure exist 10,000 km away from Namibia in the remote outback of Australia. Combining fieldwork, remote sensing, spatial pattern analysis, and process-based mathematical modeling, we demonstrate that these patterns emerge by self-organization, with no correlation with termite activity; the driving mechanism is a positive biomass–water feedback associated with water runoff and biomass-dependent infiltration rates. The remarkable match between the patterns of Australian and Namibian fairy circles and model results indicate that both patterns emerge from a nonuniform stationary instability, supporting a central universality principle of pattern-formation theory. Applied to the context of dryland vegetation, this principle predicts that different systems that go through the same instability type will show similar vegetation patterns even if the feedback mechanisms and resulting soil–water distributions are different, as we indeed found by comparing the Australian and the Namibian fairy-circle ecosystems. These results suggest that biomass–water feedbacks and resultant vegetation gap patterns are likely more common in remote drylands than is currently known.

Early Pattern Formation

1988 ◽  
Author(s):  
Keith Stewart Thomson
Keyword(s):  
Pattern Formation ◽  
Cell Function ◽  
Essential Elements ◽  
Early Event ◽  
Individual Organism ◽  
Tissue Interaction ◽  
History Of ◽  
Mechanisms Of Development ◽  
The Individual ◽  
Two Stages

The processes of development form a continuum that begins with gametogenesis and ends only with the death of the individual organism. It is therefore artificial to try to define separate phases and stages of these processes, just as it is artificial to try to separate the structural history of the embryo into a series of discrete forms through time with discrete and definable properties (let alone trying to match such artifacts to putative phylogenetic stages). But at the same time, the sequence of mechanisms of development is hierarchically organized. The major early event is the transfer of control over development itself from the purely maternal factors inherited within the egg and particularly in the egg cytoplasm, to the switching on of the zygotic genome and transfer to zygotic control of cell function, interaction and differentiation, morphogenesis and cytodifferentiation. This transfer does not occur at a single instant, nor is it easy to generalize about it even with a single group of organisms. Other landmarks are harder to find, especially ones that can be compared consistently over a range of different organisms. However, one can roughly divide the processes of development, for the purpose of organizing a discussion at least, into two main phases: early and late pattern formation phases. Early pattern formation can be defined as that part of the developmental sequence in which all the major mechanisms that control the shaping of the embryo, both its morphogenesis and cytodifferentiation, are set into place. In a vertebrate, early pattern formation would be everything from gametogenesis up to and including gastrulation, by which time all the essential elements of tissue interaction that will cause the morphogenesis of the embryo have not only been regionally defined and correctly positioned, but have started to function. Late pattern formation comprises the stages of morphogenesis and cytodifferentiation. As we will see, morphogenesis itself can be divided into two stages, early and late: roughly speaking, in the earlier part, morphogenetic pattern-controlling mechanisms are set in place, and in later stages their results are expressed.

scholarly journals Lenin and Stalin as Historians: A Comparative Analysis of their Views

2020 ◽  
Vol 10 (3) ◽  
pp. 622-642
Author(s):  
V. E. Bagdasaryan ◽  
◽  
S. I. Resnianskiy ◽  
Keyword(s):  
Foreign Policy ◽  
Comparative Analysis ◽  
Class Struggle ◽  
State Building ◽  
Russian History ◽  
Formation Theory ◽  
Historical Process ◽  
Russian State ◽  
History Of ◽  
Soviet Ideology

This article reconstructs the historical views of the leaders of the Soviet state, V.I.Lenin and I.V.Stalin, as an important component of their ideological projects. The comparison of their views on history is an indicator of differences between the Leninist and Stalinist versions of Soviet ideology. The authors conclude that the continuity of views on the history of Lenin and Stalin is maintained within the framework of the general methodological platform of Marxism (formation theory, class struggle theory, adherence to the macrosocial approach to history). Stalin developed a number of Leninist provisions regarding the understanding of history and, above all, related to the combination of Marxism with the theory of imperialism. At the same time, certain differences are found in content used — mainly the history of European revolutions by Lenin and the history of Russian state-building by Stalin. Lenin placed more emphasis on universal laws of history, while Stalin recognized the originality of the Russian historical process. There were certain differences in emphases on their interpretations of national relations and foreign policy in Russian history. Such differences in views of history were correlated with differences between the tasks Lenin and Stalin faced at different stages of the Soviet project.

“Whiteness Visible”: Critical Whiteness Studies and O’Connor’s Fiction

2020 ◽  
pp. 13-35
Author(s):  
Angela Alaimo O'Donnell
Keyword(s):  
Racial Formation ◽  
Whiteness Studies ◽  
Color Line ◽  
Formation Theory ◽  
Critical Whiteness Studies ◽  
Black Characters ◽  
Critical Whiteness ◽  
Key Concepts ◽  
History Of

Chapter 1, “‘Whiteness Visible’: Critical Whiteness Studies and O’Connor’s Fiction,” summarizes the treatment of race in O’Connor criticism from the 1970s to the present, outlines some key concepts of racial formation theory and whiteness studies, and considers their potential relevance and application to O’Connor’s work. The chapter includes a brief history of the idea of race, an examination of the so-called “color line” and the racial code observed by whites and blacks in the South, and an exploration of O’Connor’s attitudes toward that code as evident in some of her letters and in her representations of black characters in her stories. The chapter includes analysis of her first and last stories, “The Geranium” and “Judgement Day.”

scholarly journals Topical problems in the theory of planet formation: formation of planetesimals

2019 ◽  
pp. 104-121
Author(s):  
A. B. Makalkin ◽  
I. N. Ziglina ◽  
M. E. Artyushkova
Keyword(s):  
Planet Formation ◽  
State Of The Art ◽  
The State ◽  
Special Focus ◽  
Formation Theory ◽  
History Of Development ◽  
The Earth ◽  
History Of ◽  
Academy Of Sciences ◽  
Schmidt Institute

The development of the Earth’s and planets formation theory over 70 years is considered with a special focus on the history of development of this theory at the Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences (IPE RAS) where this direction of research was founded by Otto Schmidt. The state of the art of the theory is outlined. In particular, the planetesimals formation problem currently belonging to the key unsolved issues in the theory of planet formation is discussed. Recent results of the studies aimed at solving this problem at IPE RAS are presented.

HISTORY AS A PROBLEM

2020 ◽  
pp. 12-19
Author(s):  
Leonid B. Alaev ◽  
Keyword(s):  
Social Life ◽  
Economic Factor ◽  
Great Role ◽  
Formation Theory ◽  
Economic Relations ◽  
Cultural Conditions ◽  
Theoretical Approaches ◽  
The Status ◽  
History Of ◽  
Economic Indexes

This paper continues the discussion started with the review by a group of colleagues from the Southern Federal University [Volchik, Lyubsky, Makarenko, Petrov, 2019] of Leonid B. Alaev’s monograph “Issues of the History of the Orient” [Alaev, 2019] and presents author’s commentary to the review of said book by another group of teachers from the same University [Drach, Kirillov, 2020]. G. V. Drach and A. A. Kirillov doubt many author’s statements, and first of all, the critical estimation of the contemporary condition of theoretical approaches to the study of history, particularly — the degree of obsoleteness of Marxian methodology. The authors of the review do not take into consideration the fact, that recent research undermine the so- called formation theory, and propose nothing in its stead. Attempts to use other approaches (for instance, civilizational) to the World history, have produced no significant results. Meanwhile, the search for a “golden key”, for a factor capable to explain everything, proceeds. In Russian situation such a “golden key” is most often seen in an economic factor and belittling the importance of spirituality, the status of morality and formation of personality. There are no doubts, that economic relations play great role in social life, that economic indexes are very important in studying any society, but one should admit that the economic situation does not determine everything, for instance, cultural conditions, political structure and so on. The degree of hostility towards ‘bourgeois’ scholars, as compared to the Soviet times, decreased significantly, but did not vanish completely, being transmuted from ideological into geopolitical opposition. It is an obstacle on the way to candid discussion. It is necessary to separate problems, which can be discussed on the basis of common principles of strive for truth, from the views, determined by political and ideological positions of scholars, which are not disputable because the same terms and events are understood differently.

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